Qualitative evaluation of the Rey-Osterrieth Complex Figure Test in patients with progressive supranuclear palsy

Objective: In early stages of disease, the differential diagnosis between Parkinson's Disease (PD) and atypical parkinsonism, such as Progressive Supranuclear Palsy (PSP), could be challenging. Growing attention has recently been dedicated to investigating neuropsychological markers of degenerative parkinsonism. The Rey-Osterrieth Complex Figure Test (ROCFT) copy score was hypothesized able to differentiate PSP from PD. However, ROCFT is a drawing test requiring multiple cognitive abilities and it is still unknown which of them assumes an important role in PSP performance. Using a qualitative scoring system, we investigated which cognitive abilities underpin the PSP performance at the ROCFT copy trial. Moreover, we evaluated usefulness of the BQSS scores in discriminating PSP from PD. Methods: Thirty PSP-Richardson's Syndrome (PSP-RS) patients, 30 PD patients, and 30 healthy control (HC) comparable for age, education, and gender were enrolled. All subjects underwent a neuropsychological evaluation; ROCFT copy were evaluated with the 36-Point Score and with the Boston Qualitative Scoring System (BQSS). Results: PSP-RS patients performed worse in ROCFT 36-Point Score and in several BQSS scores compared to other groups. Most suitable scores discriminating PSP-RS from PD were "Perseveration" and "Vertical Expansion" of BQSS. A logistic regression model considering "Perseveration" and "Vertical Expansion" showed a diagnostic accuracy of 83,3% for PSP-RS condition. Conclusion: our findings showed that "Perseveration" and "Vertical Expansion" BQSS scores were useful in discriminating PSP-RS from PD. "Perseveration" and "Vertical Expansion" BQSS scores might be included in the cognitive evaluation along with quantitative scores when PSP diagnosis is considered.

Association mapping of Stagonospora nodorum blotch resistance in modern European winter wheat varieties

Association mapping in populations relevant for wheat breeding has a large potential for validating and fine-mapping QTLs identified in F2- or DH (double haploid)-derived populations. In this study, associations between markers in the region of QSng.sfr-3BS, a major QTL for resistance to Stagonospora nodorum glume blotch (SNG), and SNG resistance were investigated by linkage and association analyses. After increasing marker density in 240 F(5:7) recombinant inbred lines (RILs), QSng.sfr-3BS explained 43% of the genetic variance and peaked 0.6 cM proximal from the marker SUN2-3B. Association between SNG resistance and markers mapped in the region of QSng.sfr-3BS was investigated in a population of 44 modern European winter wheat varieties. Two genetically distinct subpopulations were identified within these lines. In agreement with linkage analyses, association mapping by a least squares general linear model (GLM) at marker loci in the region of QSng.sfr-3BS revealed the highest association with SNG resistance for SUN2-3B (p < 0.05). Association mapping can provide an effective mean of relating genotypes to complex quantitative phenotypes in hexaploid wheat. Linkage disequilibrium (r (2)) in chromosome 3B extended less than 0.5 cM in 44 varieties, while it extended about 30 cM in 240 RILs, based on 91 SSR and STS marker-pair comparisons. This indicated that the association mapping population had a marker resolution potential at least 390-fold higher compared to the RIL population.

Development of functional markers specific for seven Pm3 resistance alleles and their validation in the bread wheat gene pool

In the ideal case, molecular markers used for marker-assisted selection are allele-specific even if the alleles differ only by a few nucleotide polymorphisms within the coding sequence of target genes. Such 'perfect' markers are completely correlated with the trait of interest. In hexaploid wheat (Triticum aestivum L.) the Pm3 locus encodes seven alleles (Pm3a-Pm3g) conferring resistance to different races of Blumeria graminis f.sp. tritici, the agent of powdery mildew, a major disease of bread wheat. All Pm3 alleles are known at the molecular level. Here, we generated specific markers for the Pm3 alleles based on nucleotide polymorphisms of coding and adjacent non-coding regions. The specificity of these markers was validated in a collection of 93 modern or historically important cultivars and breeding lines of wheat and spelt (Triticum spelta L.). These markers confirmed the presence of the predicted Pm3 alleles in 31 varieties and lines known to carry Pm3 resistance alleles. In a few varieties, Pm3 alleles different from alleles previously described based on pathogenicity tests or tightly linked markers were observed. In all these cases, the identity of the marker-detected Pm3 alleles was confirmed by DNA sequence analysis. Pm3 markers confirmed the absence of known Pm3 resistance alleles in 54 European wheat and spelt varieties in which Pm3 alleles had not been previously identified. These results indicate that the developed markers are highly diagnostic for specific Pm3 resistance alleles in a wide range of varieties and breeding lines, and will be useful (1) for identifying Pm3 alleles in the wheat gene pool, (2) for efficient marker-assisted selection of these genes, and (3) for combining multiple Pm3 alleles within a single cultivar through transgenic approaches.

The development of multiplex simple sequence repeat (SSR) markers to complement distinctness, uniformity and stability testing of rape (Brassica napus L.) varieties

To assess the potential of multiplex SSR markers for testing distinctness, uniformity and stability of rape (Brassica napus L.) varieties, we developed three multiplex SSR sets composed of five markers each. These were used to measure the extent of diversity within and between a set of ten varieties using a fluorescence-based semi-automated detection technology. Also, we evaluated the significance of any correlation between SSRs, pedigree and five of the morphological characters currently used for statutory distinctness, uniformity and stability testing of rape varieties. An assignment test was allowed to identify 99% of the plants examined, with the correct variety based on the analysis of 48 individual plants for each variety. Principal coordinate analysis confirmed that a high degree of separation between varieties could be achieved. Varieties were separated in three groups corresponding to winter, spring and forage types. These results suggested that it should be possible to select a set of markers for obtaining a suitable separation. Diversity within varieties varied considerably, according to the variety and the locus examined. No significant correlation was found between SSR and morphological data. However, genetic distances measured by SSRs were correlated to pedigree. These results suggested that SSRs could be used for pre-screening or grouping of existing and candidate varieties, allowing the number of varieties that need to be grown for comparison to be reduced. Multiplex SSR sets gave high-throughput reproducible results, thus reducing the costs of SSR assessment. Multiplex SSR sets are a promising way forward for complementing the current variety testing system in B. napus.